Stephen Hawking passed away at his home in Cambridge, England, yesterday at age 76, after a long battle with the motor neuron disease ALS, or Lou Gehrig's Disease. The famed theoretical physicist and Cmabridge professor taught the public about black holes, relativity and beyond through his bestseller "A Brief History of Time," his other writings and his words, which came to us through a computer-generated voice with an American accent.

The wheelchair-bound genius was diagnosed with ALS at age 22 and given only a few years to live, but the astrophysicist went on to live 70 years with the fatal disease. And in those 70 years, he continued his study of space and time, teaching the world that Einstein's general theory of relativity implies space and time would have a beginning in the Big Bang and an end in black holes.

Hawking was a hero for geeks and the mainstream alike -- he was featured in shows like The Big Bang Theory and The Simpsons and his life story was portrayed by Eddie Redmayne, who won an Oscar for his role, in The Theory of Everything.

Celebs, including Redmayne, have paid tribute on social media following the great scientist/mathematician's death:

Eddie Redmayne: "We have lost a truly beautiful mind, an astonishing scientist and the funniest man I have ever had the pleasure to meet."

Katy Perry: "There’s a big black hole in my heart hours before Pi day. Rest In Peace @Steven_Hawking... See you in the next ❤️."

Piers Morgan: "RIP Professor Stephen Hawking, 76. The world’s most brilliant man, and someone who never stopped wondering ‘Why?’ This hangs on the wall outside his office at Cambridge University. It says it all. What a life, what a genius."

Jade Smith: "RIP STEPHEN HAWKING I'm gonna cry"

Mira Sorvino: "I am very saddened to hear of Stephen Hawking’s passing. His book was an enormous influence on me in college and meeting and getting to talk with him was one of the great thrills of my life. You are shining in the heavens you so loved now!"

Maria Shriver: "A new star is in the heavens tonight. Rest in peace, Stephen Hawking. Your advice and wisdom live on."

Zoe Saldana: "Farewell to a brilliant mind. Thank you for being so generous with your knowledge in the brief time you were with us. #ripstephenhawking."